BENDIX AIR DRYER

[Stormcloud]

Hi,all:

I'm going to have an air dryer installed on my MCI7...the mechanic said it likely came equipped with one when built, (he never saw one without an installed dryer) but was removed somewhere along the way.

He suggests a Bendix AD-9 dryer.

I havent used this mechanic before. He seems to know his stuff, and he maintains a small fleet of (at the moment) Prevosts, but he says he likely has more time on MCIs than he wants to admit:)

Is an AD-9 my best choice? What parts of an air dryer are 'consumable'? Do I need to carry replacement valve/filter?
Thanks for all suggestions.

Mark

[luvrbus]

That is a good dryer and no need to carry parts  just service it, some say I do mine to often I do it once a year and never have problems

[Ncbob]

Hi Mark,

I have an AD9 on my 40 year old MC5A and am perfectly happy with it. I also carry a spare element for it but haven't found the need for it after 2 years.

Based on my installation, which will probably be endorsed by the pillars of our community, you should install it before the 'ping tank' in the rear engine compartment as possible. The purpose of the air dryer is to remove excess moisture before it gets to the first tank. Manual tank pulls, to drain the 'wet' tank are ideal too.

With that advice I'll leave the rest to the experts.

cordially,

NCbob

[Dreamscape]

I have an AD9 also, just not installed yet.

I know, I know, it's on the list OK!

Let me know how you come out.


Paul

[niles500]

AD-9 is the current "state of the art"- best to go with the most current - longest sevice life - FWIW

[JackConrad]

I would install it after the ping tank and before the wet tank. The pink tank also traps oil vapors that are in the air leaving the compressor (this is why the ping tank is to be drained daily).  You want the oil vapor out of the air before it goes to the drier.  Jack

[Busted Knuckle]

I would install it after the ping tank and before the wet tank. The pink tank also traps oil vapors that are in the air leaving the compressor (this is why the ping tank is to be drained daily).  You want the oil vapor out of the air before it goes to the drier.  Jack

I agree with Jack 100%!  Also FWIW on all MCI's I have ever worked on the air dryer is usually mounted at the front behind the front axle. Which means the air goes from the compressor - to the ping tank- to the dryer at the front- then is plumbed back to the respective areas.

An AD-9 is a quite capable and common dryer.

FWIW   BK 

[TomC]

AD-9 is still available to this day on Freightliners.  Another is the AD-IP which has a spin on desiccant filter that needs to be replaced once a year.  I have the AD-4 on my Kenworth truck, which has to be rebuilt about every 200,000 miles.  But-it tells you when to rebuild it because it starts spitting often.  Good Luck, TomC

[Dreamscape]

I was studying my manuals for my Eagle last night and saw that they call it a "Pink Tank"......

Spell Check was not available back then...Hee hee

Paul

[buswarrior]

I concur, an AD9 is a fine choice and well supported by parts vendors everywhere.

Be sure that your mechanic knows the mileage of pipe required between the air drier and the compressor if he is installing it in the engine room.

Remember, mechanics usually work on existing installs, they don't "design" and may not understand all the requirments.

If he is installing up front in the traditional location, the pipe length takes care of itself.

Check for empty mounts up front, the job may be easier than originally thought!

happy coaching!
buswarrior

[Dreamscape]

I would install it after the ping tank and before the wet tank. The pink tank also traps oil vapors that are in the air leaving the compressor (this is why the ping tank is to be drained daily).  You want the oil vapor out of the air before it goes to the drier.  Jack

I had not thought of this untill I read your comment Jack!

When I do my rear brakes I am going to install the AD 9 at that time.

My question is this, what type of hose do I use after the ping to the dryer back to the wet tank?

I will be installing the dryer in the LH corner by the electrical panel in the rear of our Eagle. So the hose length won't be too bad.

Thanks,

Paul

[JackConrad]

I can only tell you what is on our bus (was on it when we purchased it). The hose from the compressor to the ping tank has a braided SS jacket abd crimped on fittings. From the ping tank to the dryer is a rubber hose with crimped on fittings. From dryer to wet tank (only a few inches) is a metal line with compression type fittings.  Jack

[Dreamscape]

Thanks Jack,

The Bendix site does not specify any type, only minimum size of 3/16" IS dia.

I was thinking that 1/2" rubber would work.

[JackConrad]

Just looking at the outside diameter, I would say our air line from compressor to ping tank and from ping tank to air dryer is 5/8" inside diameter. Metal line from dryer to wet tank also appears to be 5/8",  Jack

[luvrbus]

Paul, use DOT approved poly tubing will last longer than rubber and cheaper